/// <summary>
/// This is used to expand one or more weeks by day of the week
/// </summary>
/// <param name="r">A reference to the recurrence</param>
/// <param name="dates">A reference to the collection of current instances that have been generated</param>
/// <returns>The number of instances in the collection. If zero, subsequent rules don't have to be
/// checked as there's nothing else to do.</returns>
/// <remarks>If an expanded date is invalid, it will be discarded</remarks>
public static int ByDayInWeeks(Recurrence r, RecurDateTimeCollection dates)
{
RecurDateTime rdt, rdtNew;
int expIdx, count = dates.Count;
DayInstanceCollection byDay = r.ByDay;
// Don't bother if either collection is empty
if (count != 0 && byDay.Count != 0)
{
for (int idx = 0; idx < count; idx++)
{
rdt = dates[0];
dates.RemoveAt(0);
// If not valid, discard it
if (!rdt.IsValidDate())
{
continue;
}
// Expand the date/time by adding a new entry for each day of the week. As with filtering,
// the instance number is ignored as it isn't useful here. For this, the "week" is the seven
// day period starting on the occurrence date.
for (expIdx = 0; expIdx < byDay.Count; expIdx++)
{
rdtNew = new RecurDateTime(rdt);
rdtNew.AddDays((((int)byDay[expIdx].DayOfWeek + 7 - (int)r.WeekStart) % 7) -
(((int)rdt.DayOfWeek + 7 - (int)r.WeekStart) % 7));
dates.Add(rdtNew);
}
}
}
return(dates.Count);
}
/// <summary>
/// This is used to expand the yearly frequency by day of the week
/// </summary>
/// <param name="r">A reference to the recurrence</param>
/// <param name="dates">A reference to the collection of current instances that have been generated</param>
/// <returns>The number of instances in the collection. If zero, subsequent rules don't have to be
/// checked as there's nothing else to do.</returns>
/// <remarks>If an expanded date is invalid, it will be discarded</remarks>
public int ByDay(Recurrence r, RecurDateTimeCollection dates)
{
RecurDateTime rdt, rdtNew;
DayOfWeek dow;
int expIdx, instance, count = dates.Count;
DayInstanceCollection byDay = r.ByDay;
// Don't bother if either collection is empty
if (count != 0 && byDay.Count != 0)
{
for (int idx = 0; idx < count; idx++)
{
rdt = dates[0];
dates.RemoveAt(0);
// Expand the date/time by adding a new entry for each week day instance specified
for (expIdx = 0; expIdx < byDay.Count; expIdx++)
{
instance = byDay[expIdx].Instance;
dow = byDay[expIdx].DayOfWeek;
if (instance == 0)
{
// Expand to every specified day of the week in the year
rdtNew = new RecurDateTime(rdt);
rdtNew.Month = 0;
rdtNew.Day = 1;
rdtNew.AddDays(((int)dow + 7 - (int)rdtNew.DayOfWeek) % 7);
while (rdtNew.Year == rdt.Year)
{
dates.Add(new RecurDateTime(rdtNew));
rdtNew.AddDays(7);
}
continue;
}
if (instance > 0)
{
// Add the nth instance of the day of the week
rdtNew = new RecurDateTime(rdt);
rdtNew.Month = 0;
rdtNew.Day = 1;
rdtNew.AddDays((((int)dow + 7 - (int)rdtNew.DayOfWeek) % 7) + ((instance - 1) * 7));
}
else
{
// Add the nth instance of the day of the week from the end of the year
rdtNew = new RecurDateTime(rdt);
rdtNew.Month = 11;
rdtNew.Day = 31;
rdtNew.AddDays(0 - (((int)rdtNew.DayOfWeek + 7 - (int)dow) % 7) + ((instance + 1) * 7));
}
// If not in the year, discard it
if (rdtNew.Year != rdt.Year)
{
continue;
}
dates.Add(new RecurDateTime(rdtNew));
}
}
}
return(dates.Count);
}